Electrical connector assembly

ABSTRACT

An electrical connector assembly including a box-like housing with open ends and a plurality of flat cable electrical connectors retained in the housing and individually releasable therefrom, by releasable latching elements, with each of the connectors being adapted to electrically receive a multiconductor flat cable wherein the individual conductors are accessible through apertures in the cable and each connector includes a two piece dielectric insert housing a plurality of contacts with hook-like tails facing a common lateral direction and insertable through the apertures for electrical access to the conductors in the cable.

United States Patent 1191 Provinsky [451 Dec. 17, 1974 1 1 ELECTRICALCONNECTOR ASSEMBLY [75] Inventor: Jerry Provinsky, Westmont, Ill.

[73] Assignee: Bunker Ramo Corporation, Oak

Brook, Ill.

{22] Filed: Sept. 17, 1973 [21] Appl. No.: 397,994

[52] US. Cl. 339/198 GA, 339/208, 339/210 R,

339/17 51 1111. c1 H0lr 9/00 58 Field of Search 339/198, 206, 207, 208,

339/210,215, 176 R, 176 M, 176 MP, 258 P, 339/21" R, 17

[56] References Cited UNITED STATES PATENTS 3,173,062 3/1965 v Smith eta1. 339/198 P 3,378,808 4/1968 French 339/176 MF 3,439,313 4/1969Fischer et a1. 339/198 R 3,547,274 12/1970 Sosinkski 339/198 GA X3,548,367 12/1970 Brvetsch 339/258 P Primary Examiner-Roy D. FrazierAssistant ExaminerRobert A. Hafer Attorney, Agent, or FirmWilliam Lohff;Frederick M. Arbuckle [57] ABSTRACT An electrical connector assemblyincluding a box-like housing with open ends and a plurality of flatcable electrical connectors retained in the housing and individuallyreleasable therefrom, by releasable latching elements, with each of theconnectors being adapted to electrically receive a multi-conductor flatcable wherein the individual conductors are accessible through aperturesin the cable and each connector includes a two piece dielectric inserthousing a plurality of contacts with hook-like tails facing a commonlateral direction and insertable through the apertures for electricalaccess to the conductors in the cable.

16 Claims, 10 Drawing Figures PATENTEL JED] H974 4,790

MET 1 [1F 2 PAIENIEUUEC 111914 SHEET 2 or 2 II. M

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l ELECTRICAL CONNECTOR ASSEMBLY This invention relates to an electricalconnector assembly and electrical connectors therefor adapted forconnection to flat cables with apertures providing electrical access tothe individual conductors of each cable. The invention herein describedwas made in the course of or under a contract or subcontract thereunderwith the United States Government.

BACKGROUND OF THE INVENTION In connecting a plurality of conductors in aflat cable to existing electrical connectors adapted for such cables,the individual conductors are commonly soldered or otherwise applied tothe individual contacts in the connector. Often the contacts are closelyspaced in a row in the connector to generally match the spacing of theconductors.

When two or more of these connectors are closely spaced together in aside-by-side relation, one of the problems that can occur concerns thedifficulty in providing reliable solder connections to the individualcontacts within the limited spacing available. In some instances, themetallic surfaces of the individual conductors are not completelysoldered electrically to the adjacent contact tail or excess solder maybe used which can cause electrical shorts.

Another problem associated with mounted assemblies of two or moreconnectors affixed to a plurality of flat cables is that it can bedifficult to remove one connector from the assembly without initiallyremoving all of the connectors. Since it often becomes desirable forreplacement or maintenance purposes to remove individual connectors fromthe assembly, improvements are desirable in mounting two ormore'connectors together in an assembly which will permit removal orrelease of individual connectors.

SUMMARY Briefly, the invention is directed to electrical connectorassemblies in which a plurality of electrical connectors are connectedto a plurality of flat cables and individually releasable from theassembly. The invention is further directed to individual connectorswith retention means on opposite extremities which cooperate with aportion or portions of the assembly to permit the release of anindividual connector. Also, the invention is directed to electricalconnectors constructed of twopart inserts in which one part serves assupport for internally interconnecting the contacts to conductors in aflat cable, after which the second part is installed to complete theconnector.

In the inventive assembly, a plurality of connectors are retained withinthe hollow interior of a box-like housing with each connector andadjacent portions of the housing provided with retention means includinginwardly yieldable latching elements and adjacent shoulder means overwhich the latching elements are snapped to permit release of individualconnectors. The insulating inserts of individual connectors are of twopart construction with each part advantageously forming one side andportions of the opposite ends and front and rear faces of the insert. Aplurality of contacts are arranged in at least one row along theinternal surface of one part of the insert and include hook-like tailsspaced inwardly from the'rear face of the insert and oriented laterallyin a common direction towards the other insert point. Prior to theconnector being inserted in the assembly housing, a flat cable withapertures and adjoining exposed solder pads electrically connected tothe conductors in the cable is placed over hook-like tails of thecontacts for electrical engagement as by soldering between the tails andsolder pads. The insert parts further include posts on at least one partand aligned apertures on at least the other part through which the postsare inserted for retention of the two parts together followinginstallation and interconnection of the cable.

Among the several advantages provided by the invention, one is that eachconnector with an installed cable can be individually inserted in acompact arrangement in the assembly housing and subsequently removedindividually. I

Another advantage is that removal of the individual connectors can beaccomplished manually or by simple tools.

A further advantage is that the individual connectors BRIEF DESCRIPTIONOF THE DRAWINGS FIG. 1 is a perspective view of an electrical connectorassembly of the invention.

FIG. 2 is an internal side view partially in cross section along line2-2 of FIG. 1.

FIG. 3 is a partial plan view of one end of a flat cable.

FIG. 4 is a partial perspective view of one connector utilized in theassembly of FIG. 1.

FIG. 5 is an end sectional view along line 5-5 of FIG. 4.

FIG. 6 is an end sectional view along line 66 of FIG. 7 is a partialperspective view of a second embodiment of the invention.

FIG. 8 is a partial side view along line 8-8 of FIG. 7.

FIG. 9 is a partial perspective view of one end of a connector of FIG.7.

FIG. 10 is an end sectional view along line 10-10 of FIG. 9.

DETAILED DESCRIPTION In FIGS. 1-2, the connector assembly 8 of theinvention is represented as including a box-like housing 10 with upperand lower open ends 12 and 14, respectively, and four raised sides 16-19protruding from base 20. Each pair of sides are opposite and form arectangular-shaped hollow interior 21 within housing 10. Apertures 22and 24 visible in FIG. I serve for mounting the assembly to a panel orother external support (not shown) while aperture 25 serves to receive ajack screw. A plurality of electrical'connectors 26-32 are arranged inhollow interior 21 in a side-by-side relation so that collectively theyform a rectangular shape 33 sized to fit within hollow interior 21. Asillustrated, representative connector 28 includes a dielectric insert 34with ends 35-36 adjacent opposite sides 16-18 of housing and with sides37-38 adjoining connectors 27 and 29, respectively. Connector 28includes an upper face 39 with a plurality of upper openings 40 arrangedin a row between ends 35-36 for engagement with a mating connector (notshown). Each of the connectors also includes a lower portion with rearface 41 to receive flat cable 42.

As illustrated in FIG. 3, cable 42 includes a plurality of apertures 43with solder pads 44 at end 45 of the cable to provide electrical accessto the individual conductors (not shown) arranged in a parallel patternbetween the sides of the cable. Apertures 46 are provided to retain thecable in the connector as illustrated in FIG. 6.

In the sectional view of FIG. 2, the side 37 of connector 28 is shownmounted in housing 10 but releasable rearwardly from the housing. Asillustrated, representative connector 28 includes projections 48-49 onends 35-36, respectively, providing opposite shoulders 50-51 and 52-53to form one of the two retention members for retaining the connector inthe housing. Housing 10 further includes an integrally-formed,individually-yieldable, vertically-oriented pair of latching elementsrepresented by opposite tines 54-55 with upper free ends 56-57 inclinedinwardly to bear against the lower shoulders of projections 48-49. Tines54-55 are individual members of a plurality of tines arranged in tworows at the bottom of the hollow interior 21 of housing 10 along sides16 and 18. Free ends 56-57 of tines 54-55 are spaced apart fromsidewalls l6 and 18 to permit outward deflection during the insertion ofthe individual connectors and rear openings 58-59 are providedrearwardly as access means to permit insertion of a probe (not shown)for outward deflection of the time and release of the individualconnector. Frontwardly disposed from and spaced apart from tines 54-55are shoulders 60-61 which in combination with the tines form grooves62-63 to receive projections 48-49. During the insertion of theconnector, projections 48-49 ride over the tines 54-55 and snap intogrooves 62-63 thereby retaining the connector in the housing butpermitting its rear release therefrom.

FIG. 4 isillustrative of the general shape of connector 28 with itsfront openings 40 and multi-piece construction of insert 34 with theindividual insert members 34a and 34b forming portions of openings 40.In assembling each insert member to form the completed insert, eachconnector member is fastened to the other by means of aligned pins andapertures represented by pins or posts 64-65 and apertures 66-67. Asillustrated in FIG. 6, the ends of the pins are enlarged to permanentlyaffix the insert members together.

In FIG. 5, contact 72 is representative of a plurality of contactsarranged in a row between ends 35-36 and retained in insert 34. Contact72 is positioned in enlarged cavity 73 which extends between opening 40and lower opening 74, the latter being sized to receive cable 42 andbeing therefore generally an elongated opening. Upper opening 40 is of aclosed entry construction and frontwardly chamfered for guiding the pinof a mating contact (not shown) into the upper active portion of contact72 represented by contact socket 75 aligned below opening 40 and inclose relation to sides 37-38. Contact 72 includes a rear tall 76adapted to be inserted into aperture 43 of cable 42 and electricallyengage solder pads 44. Tail 76 includes hook 77 with end 78 extendinglaterally within the sideto-side confines of cavity 73. The purpose ofapertures 46 in cable 42 is demonstrated in FIG. 6 wherein pin 65 isinserted through apertures 46 and 67 and thereafter flattened topermanently affix the lower portions of insert members 34a and 34btogether. Front pin 64 is inserted through aperture 66 and thereafterflattened to affix the upper portions of the insert 34 together.

By constructing each of the connectors 26-32 of twopiece construction,contacts 72 can be easily inserted in cavities 73 of insert 34a withhooks 77 all extending in a common lateral direction. Flat cable 42 canthen be inserted over hooks 77 and pins 65 in one step after whichsolder pads 44 are soldered to tails 76. The second half 34b of insert34 can then be mounted to complete the assembly. In the resultantassembly, contact tails 76 are held within the confines of insert 34 andrearwardly protected against accidental shorting or other engagement bymetallic members. Advantageously, each of the molded side members 34aand 34b include pins 64-65 as well as apertures 66-67 arranged in analternating pattern by upper and lower pins and apertures and includeopposite portions of openings 40 and 74 and cavities 73 so that bothside members can be formed in the same mold. Each of the pins 64-65 ofone member are positioned for alignment within apertures 66-67 of theother member which facilitates easy mounting of the two memberstogether.

A second embodiment of the invention is illustrated in FIGS. 7-10.Housing in FIG. 7 includes base 91 with apertures 92-93, sidewalls 94-95and hollow interior 96. Sidewall 95 is recessed to form ledge 97 withkeyways 98 for lateral alignment of connectors 100. As illustrated, eachconnector includes a hex or projection 101 with latch element orextension 102 shaped to abut against ledge 97 for retention of theconnector in the housing. Slot 103, as partially illustrated in FIG. 7,permits the inward flexing of latch element 102 to release the connectorfrom the housing. Similar to connector 28, connector includes a frontface 104 with a plurality of upper openings 105 to receive a matingconnector. Connectors 100 are arranged in a side-by-side relation in asimilar manner to connectors 26-32. In the sectional view of FIG. 8, theshape of hollow interior 96 is further illustrated including keyways 98and recessed ledges 97. Rearwardly disposed in hollow interior 96 isshoulder 106 which collectively with sidewall 95 and ledge 97 forms aprojection for retaining connectors 100 in housing 90. The projectionforms abutment surfaces for engagement with latch element 102 and lowershoulder 109 which collectively form groove 110 as illustrated in FIG.9. Projection 101 includes ends 1 1 1-1 12 integrally formed on theconnector insert with latch element 102 generally positioned abouthalfway between the ends so that upper portion 1 13 provides an exposedarea which can be manually deflected inwardly carrying tine 102 forrelease of the connector.

As illustrated in FIGS. 9-10, contacts are positioned in cavities 116below opening 105 to receive mating contact members. Contact 115includes collar 117 for retention purposes and a lower hook 118extending through aperture 43 on cable 42 for electrical connection ofone of the individual conductors. Connector member 100!) extends belowconnector member 100a and is provided with individual narrow pockets 119open laterally towards member 100a and formed by barrier walls 123.Hooks 118 in pockets 119 are oriented towards side member 100a andextend below side member 100a beyond pockets 119 to receive flat cable42. In this manner, contacts 115 are restricted in rotational movementand provide hooks 118 over which cable 42 can be inserted in one step.

A lower portion 120 with barrier walls 123 is further provided withsupport 121 to limit the lateral positioning of cable 42 prior to theformation of the solder connection with hook 118. Strain relief pin 122is positioned to pass through aperture 46 on cable 42 and provide strainrelief for the cable. After termination of cable 42 to connector 100cavity below connector member 100a can be potted or otherwise enclosedin a manner known to the art after which the individual connectors areinserted into housing 90. Following installation of flat cables 42individually in connectors 2632 or 100, the connectors are rearwardlyinserted in housing or 90 and snapped into position. In the resultantarrangement, the connectors are in a side-byside relation and can beindividually released for maintenance or other purposes.

While the invention has been particularly shown and described above withreference to a preferred embodiment thereof, it will be recognized bythose skilled in the art that the principals of this invention may beapplied in other similar devices and that the foregoing and otherchanges in form and details may be made therein without departing fromthe spirit and scope of the invention.

What is claimed is:

1. An electrical connector assembly comprising a box-like housing withupper and lower open ends and at least one pair of opposite outer sides,

a plurality of electrical connectors including a plurality ofmulti-piece dielectric insertswith opposite ends disposed adjacent saidpair of opposite sides of said housing to form two sets of retentionmembers, and a plurality of electrical contacts arranged in a rowbetween said ends and retained in each of said inserts, said connectorsbeing disposed in sideby-side relation within said sides, facing saidupper end for engagement with mating connectors and including lowerportions for electrical engagement with electrical conductors, each ofsaid connectors being capable of rearwardly receiving a flatmulticonductor cable with an end having a plurality of apertures, aportion thereof providing electrical access to the conductors, each ofsaid inserts including a lower portion with an elongated opening sizedfor entry of said cable into said insert, and each of said contactsincluding a lower tail formed as a hook to engage one of said aperturesand thereby provide electrical engagement with one of said conductors,and

means for releasably retaining said connectors individually in saidhousing including a row of integrally-formed, individually yieldablelatching elements and spaced apart shoulder means to form groovestherebetween on one of said retention members in each of said two sets,projection means with upper and lower shoulders on the other of saidretention members to ride over the latching elements and snap into saidgrooves, and access means in at least one of said retention members forrelease of said latching elements.

2. The connector assembly of claim 1 wherein the opposite sides of saidone pair include upwardly facing recessed ledges and each of said insertends includes an outwardly projecting, inwardly yieldable latchingelement having one end integrally joined to said insert and an armportion extending above said ledge and externally exposed for movementinwardly for release of said latching element.

3. The connector assembly of claim 2 wherein each of said insertion endsincludes a vertical key including said latching element, and saidadjacent side includes a vertical keyway extending upwardly to saidledge for insertion of said key, the vertical keys and vertical keywaysof the inserts and housing providing lateral alignment of the inserts inthe housing.

4. The connector assembly of claim 3 wherein each insert includes a pairof individually molded side members, each having portions of said keys.

5. The connector assembly of claim 1 wherein said contacts include reartails with laterally extending hooks, the extension of said hooks beingwithin the side-to-side confines of said insert.

6. The electrical connector assembly of claim 1 wherein each of saiddielectric inserts includes a pair of side members with oppositelyaligned apertures and posts, the posts extending inwardly across saidinsert for entry into said apertures to secure said members togetherwith at least one of said posts being positioned for insertion throughone of said apertures in said cable for retention of said cable in saidinsert.

7. The electrical connector assembly of claim 1 wherein said housingincludes an outer flange with means for mounting said housing to anexternal support.

8. An electrical connector for rearwardly receiving a flatmulti-conductor cable having an end with apertures affording electricalaccess to individual conductors, said connector comprising a dielectricinsert with front and rear faces, a plurality of upper openings in a rowalong said front face, an elongated lower opening along said rear facefor entry of said cable, a plurality of internal cavities extendingbetween said upper openings and said lower opening, and a plurality ofelectrical contacts disposed in said cavities with upper active portionsfacing said upper openings and lower tail portions 'with laterallyextending hooks shaped to be inserted into at least a portion of saidapertures of said cable andelectrically engage said conductors in saidcable,

said insert further including a pair of individually molded side memberseach providing an opposite portion of said upper openings and cavities,the side members including a plurality of side apertures and inwardlyextending side posts with at least one of said posts on one side memberbeing aligned with one of said apertures on the other side member forentry into said aperture for retention of the side members,

said hooks all facing one of said members and over which the aperturedend of the cable can be inserted, and

one of said side members extending below the other side member andincluding narrow pockets open laterally towards the other member toreceive at least a portion of the contact tail portions and therebyrestrict the contacts from rotation with the ends of the hooks beingexposed laterally beyond the pockets to receive said cable.

9. The electrical connector of claim 8 wherein the insert includes alower portion with said elongated lower opening which when the cable isinserted into the opening prevents accidental electrical access to theconductors through the apertures.

10. The electrical connector of claim 8 wherein said insert includesopposite ends with inwardly yieldable latching elements for releasableretention of said insert housing.

11. The electrical connector of claim 10 wherein said one side memberincludes barrier walls forming said pockets and providing side supportfor said cable.

12. The electrical connector of claim 9 wherein said insert includesopposite ends with projection means providing front and rear facingshoulders for retention of said connector in a housing.

13. The electrical connector of claim 12 wherein said posts andapertures in each side member are disposed in upper and lower rows withthe posts and apertures being in an alternating arrangement in each ofsaid rows.

14. An electrical connector for rearwardly receiving a flatmulti-conductor cable having an end with apertures affording electricalaccess to individual conductors, said connector comprising a dielectricinsert with front and rear faces, a plurality of upper openings in a rowalong said front face, an elongated lower opening along said rear facefor entry of said cable, a plurality of internal cavities extendingbetween said upper openings and said lower opening, and a plurality ofelectrical contacts disposed in said cavities with upper active portionsfacing said upper openings and lower tail portions with hooks shaped tobe inserted into at least a portion of said apertures of said cable andelectrically engage said conductors in said cable,

said insert further including a pair of individually molded side memberseach providing an opposite portion of said upper openings and cavities,one of the side members including narrow pockets open laterally towardsthe other member to receive at least a portion of the contact tailportions and thereby restrict the contacts from rotation with the endsof the hooks being exposed laterally beyond the pocket to receive saidcable.

15. The electrical connector assembly of claim 14 wherein said one sidemember includes barrier walls forming said pockets and providing sidesupport for said cable.

16. The electrical connector of claim 15 wherein said insert includesopposite ends with means for latching said connector to an externalhousing.

1. An electrical connector assembly comprising a box-like housing withupper and lower open ends and at least one pair of opposite outer sides,a plurality of electrical connectors including a plurality ofmulti-piece dielectric inserts with opposite ends disposed adjacent saidpair of opposite sides of said housing to form two sets of retentionmembers, and a plurality of electrical contacts arranged in a rowbetween said ends and retained in each of said inserts, said connectorsbeing disposed in sideby-side relation within said sides, facing saidupper end for engagement with mating connectors and including lowerportions for electrical engagement with electrical conductors, each ofsaid connectors being capable of rearwardly receiving a flatmulti-conductor cable with an end having a plurality of apertures, aportion thereof providing electrical access to the conductors, each ofsaid inserts including a lower portion with an elongated opening sizedfor entry of said cable into said insert, and each of said contactsincluding a lower tail formed as a hook to engage one of said aperturesand thereby provide electrical engagement with one of said conductors,and means for releasably retaining said connectors individually in saidhousing including a row of integrally-formed, individually yieldablelatching elements and spaced apart shoulder means to form groovestherebetween on one of said retention members in each of said two sets,projection means with upper and lower shoulders on the other of saidretention members to ride over the latching elements and snap into saidgrooves, and access means in at least one of said retention members forrelease of said latching elements.
 2. The connector assembly of claim 1wherein the opposite sides of said one pair include upwardly facingrecessed ledges and each of said insert ends includes an outwardlyprojecting, inwardly yieldable latching element having one endintegrally joined to said insert and an arm portion extending above saidledge and externally exposed for movement inwardly for release of saidlatching element.
 3. The connector assembly of claim 2 wherein each ofsaid insertion ends includes a vertical key including said latchingelement, and said adjacent side includes a vertical keyway extendingupwardly to said ledge for insertion of said key, the vertical keys andvertical keyways of the inserts and housing providing lateral alignmentof the inserts in the housing.
 4. The connector assembly of claim 3wherein each insert includes a pair of individually molded side members,each having portions of said keys.
 5. The connector assembly of claim 1wherein said contacts include rear tails with laterally extending hooks,the extension of said hooks being within the side-to-side confines ofsaid insert.
 6. The electrical connector assembly of claim 1 whereineach of said dielectric inserts includes a pair of side members withoppositely aligned apertures and posts, the posts extending inwardlyacross said insert for entry into said apertures to secure said memberstogether with at least one of said posts being positioned for insertionthrough one of said apertures in said cable for retention of said cablein said insert.
 7. The electrical connector assembly of claim 1 whereinsaid housing includes an outer flange with means for mounting saidhousing to an external support.
 8. An electrical connector forrearwardly receiving a flat multi-conductor cable having an end withapertures affording electrical access to individual conductors, saidconnector comprising a dielectric insert with front and rear faces, aplurality of upper openings in a row along said front face, an elongatedlower opening along said rear face for entry of said cable, a pluralityof internal cavities extending between said upper openings and saidlower opening, and a plurality of electrical contacts disposed in saidcavities with upper active portions facing said upper openings and lowertail portions with laterally extending hooks shaped to be inserted intoat least a portion of said apertures of said cable and electricallyengage said conductors in said cable, said insert further including apair of individually molded side members each providing an oppositeportion of said upper openings and cavities, the side members includinga plurality of side apertures and inwardly extending side posts with atleast one of said posts on one side member being aligned with one ofsaid apertures on the other side member for entry into said aperture forretention of the side members, said hooks all facing one of said membersand over which the apertured end of the cable can be inserted, and oneof said side members extending below the other side member and includingnarrow pockets open laterally towards the other member to receive atleast a portion of the contact tail portions and thereby restrict thecontacts from rotation with the ends of the hooks being exposedlaterally beyond the pockets to receive said cable.
 9. The electricalconnector of claim 8 wherein the insert includes a lower portion withsaid elongated lower opening which when the cable is inserted into theopening prevents accidental electrical access to the conductors throughthe apertures.
 10. The electrical connector of claim 8 wherein saidinsert includes opposite ends with inwardly yieldable latching elementsfor releasable retention of said insert housing.
 11. The electricalconnector of claim 10 wherein said one side member includes barrierwalls forming said pockets and providing side support for said cable.12. The electrical connector of claim 9 wherein said insert includesopposite ends with projection means providing front and rear facingshoulders for retention of said connector in a housing.
 13. Theelectrical connector of claim 12 wherein said posts and apertures ineach side member are disposed in upper and lower rows with the posts andapertures being in an alternating arrangement in each of said rows. 14.An electrical connector for rearwardly receiving a flat multi-conductorcable having an end with apertures affording electrical access toindividual conductors, said connector comprising a dielectric insertwith front and rear faces, a plurality of upper openings in a row alongsaid front face, an elongated lower opening along said rear face forentry of said cable, a plurality of internal cavities extending betweensaid upper openings and said lower opening, and a plurality ofelectrical contacts disposed in said cavities with upper active portionsfacing said upper openings and lower tail portions with hooks shaped tobe inserted into at least a portion of said apertures of said cable andelectrically engage said conductors in said cable, said insert furtherincluding a pair of individually molded side members each providing anopposite portion of said upper openings and cavities, one of the sidemembers including narrow pockets open laterally towards the other memberto receive at least a portion of the contact tail portions and therebyrestrict the contacts from rotation with the ends of the hooks beingexposed laterally beyond the pocket to receive said cable.
 15. Theelectrical connector assembly of claim 14 wherein said one side memberincludes barrier walls forming said pockets and providing side supportfor said cable.
 16. The electrical connector of claim 15 wherein saidinsert includes opposite ends with means for latching said connector toan external housing.